Import sercomm.c from osmocom-bb

This imports the file src/target/firmware/comm/sercomm.c from
osmocom-bb.git without introducing any modifications.  It will not even
be built yet, as Makefile integration is intentionally left until it has
been adapted to work inside libosmocore.

Change-Id: I9ee199381c7b5986a9540d124836cdddd0f66c86

1 files changed, 61 insertions, 0 deletions

diff --git a/include/osmocom/core/sercomm.h b/include/osmocom/core/sercomm.h
new file mode 100644
index 00000000..21f715ba
--- /dev/null
+++ b/include/osmocom/core/sercomm.h
@@ -0,0 +1,61 @@
+#ifndef _SERCOMM_H
+#define _SERCOMM_H
+
+#include <osmocom/core/msgb.h>
+
+#define HDLC_FLAG	0x7E
+#define HDLC_ESCAPE	0x7D
+
+#define HDLC_C_UI	0x03
+#define HDLC_C_P_BIT	(1 << 4)
+#define HDLC_C_F_BIT	(1 << 4)
+
+/* a low sercomm_dlci means high priority.  A high DLCI means low priority */
+enum sercomm_dlci {
+	SC_DLCI_HIGHEST = 0,
+	SC_DLCI_DEBUG   = 4,
+	SC_DLCI_L1A_L23 = 5,
+	SC_DLCI_LOADER  = 9,
+	SC_DLCI_CONSOLE = 10,
+	SC_DLCI_ECHO    = 128,
+	_SC_DLCI_MAX
+};
+
+#ifndef HOST_BUILD
+#include <uart.h>
+/* helper functions for target */
+void sercomm_bind_uart(int uart);
+int sercomm_get_uart(void);
+void sercomm_change_speed(enum uart_baudrate bdrt);
+#endif
+
+void sercomm_init(void);
+int sercomm_initialized(void);
+
+/* User Interface: Tx */
+
+/* user interface for transmitting messages for a given DLCI */
+void sercomm_sendmsg(uint8_t dlci, struct msgb *msg);
+/* how deep is the Tx queue for a given DLCI */
+unsigned int sercomm_tx_queue_depth(uint8_t dlci);
+
+/* User Interface: Rx */
+
+/* receiving messages for a given DLCI */
+typedef void (*dlci_cb_t)(uint8_t dlci, struct msgb *msg);
+int sercomm_register_rx_cb(uint8_t dlci, dlci_cb_t cb);
+
+/* Driver Interface */
+
+/* fetch one octet of to-be-transmitted serial data. returns 0 if no more data */
+int sercomm_drv_pull(uint8_t *ch);
+/* the driver has received one byte, pass it into sercomm layer.
+   returns 1 in case of success, 0 in case of unrecognized char */
+int sercomm_drv_rx_char(uint8_t ch);
+
+static inline struct msgb *sercomm_alloc_msgb(unsigned int len)
+{
+	return msgb_alloc_headroom(len+4, 4, "sercomm_tx");
+}
+
+#endif /* _SERCOMM_H */